Operators of vehicles are exposed to large amounts of information from multiple information sources around the vehicle and from within the vehicle itself. The constant flow of information arises from different sources such as road signs, adjacent vehicles, maps, navigation systems, commercial billboards, traffic information, radio stations, and vehicle information. In addition to maintaining a constant speed and monitoring information provided by the vehicle, for example from dials on a dashboard, vehicle operators need to have full control of the surroundings in order to drive safely. This means that large portions of information need to be interpreted in real-time in by the vehicle operator.
In prior art it is known to provide information to vehicle drivers in multiple ways, including visual indications, tactile feedback, and audio playback. Further it is well known how to combine such systems which for example is done in vehicle navigation systems. Information presented to the operator through means of displays or other visual means often comprises distance, direction, or indicative information presenting to the operator a place or direction to associate with the information. Examples are road signs telling the user where the next exit leads or a display within a vehicle navigation system that presents a direction to a specific destination.
Information provided to the operator through speakers or any other form of audio playback is often more general and needs to be associated with events or places in a way that is intuitive for the vehicle operator. This presents multiple problems when an audio representation needs to be associated with actions, directions, distance, or any other subject or item. This has previously been addressed by association where for example a fasten seatbelt sound played in a vehicle is associated to the action of fastening the seat belt. The operator associates this sound with a known course of action, i.e., fastening his or her seatbelt. However, if more complex information shall be presented such associations are not beneficial due to the high level of knowledge and association recognition required in order to interpret the information.
Other solutions comprise spoken information describing the direction, distance, or associated action with the played sound. Examples are navigation systems wherein the user is told to take the third exit to the right, or to leave the interstate in 400 meters. Addition of such information provides guidance for the vehicle operator about where the exit is located but still is dependent on the operator's ability to estimate a distance, such as 400 meters.
There are efforts to address association by embedding information in sound presented in prior art wherein it is known to provide solutions for three-dimensional sound distribution within the passenger compartment of a vehicle. Previous solutions for example describe navigation systems, such as GPS navigation systems, aimed to help a vehicle operator to find the right way to a point of interest through directional sound. Examples of such solutions include creation of directional sound within a passenger compartment where a sound is played with a time difference between speakers mounted diagonally within the passenger compartment. The operator of the vehicle thereby is exposed to a sound that appears to be moving from the far back to the front of the car in the direction of for example a point of interest. The point of interest can for example be a restaurant or gas station and the sound could for example serve the purpose of informing the vehicle operator that there is a gas station nearby.
Directional sound can for example utilize ultrasound to carry the normal sound. Ultrasound has a dB range from 20 kHz up to several gigahertzes, the latter being very high. The dB rates that are suitable to expose a human to without endangering the creation of a hazardous environment are limited, for example excess of 120 dB might lead to hearing losses and above 180 dB might even be fatal. This means that presenting direction sound close to the ears of a vehicle operator in the way described by the prior art is not very suitable and could potentially be dangerous to the user.
Although three-dimensional (3-D) sound has been discussed in prior art, no solution to all the aforementioned problems has been developed. For example, 3D sound as described by the prior art is not adapted to provide a real 3D experience for the vehicle operator and thereby fails to provide important information to the driver in an adequate way.
Most systems presented by prior art furthermore utilize sound sources that are already present in the vehicle in order to provide 3D sound. By using for example a stereo device it is difficult to adapt the sound specifically for the vehicle operator due to the position of the speakers. Such systems often aim at providing 3D sound for everyone in the vehicle and not only the operator. Furthermore, this leads to situations wherein the vehicle operator and passengers might interpret the embedded information in different ways which easily creates confusion.